Same difference

This phrase has aggravated me since the first time I heard it. Those who use it justify it as being akin to, “...same thing!” which has never sat right me. In my opinion, something is either the same or it is different. By this token, “Same difference!” sounds like a junk phrase that sounds correct but is, in fact, meaningless. It grates for me as much as “irregardless”.

Am I incorrect? Is there any validity to this phrase, outside of modern colloquialism?

Oh, and as for "I could care less", I don't think it means that you do actually care a little. I've always understood it to be a sarcastic utterance, and as such, correctly meaning the same thing as "I couldn't care less", the type of thing that in days past would only be mumbled by a petulant teenager, usually preceded by "Oh, like...".

And yes, I do realize that today, many use "I could care less" carelessly, without much thought or any sarcastic inflection.

I can certainly see why some might find the oxymoron "same difference" irritating, but I have to agree with Will; it does make a certain kind of sense. "Same difference" does not mean that two things are the same. It means that two things actually are different, but for the purpose at hand, they are the same. To put it another way, yes, they're different but it doesn't matter.

@dave Yes, I most certainly despise that phrase! As David Storey pointed out, it is plain grammatically incorrect to me. I do use the phrase, "I couldn't care less," as I think the idea behind the phrase is that one has reached the absolute zero of their level of caring, so it cannot be any less than that. To me, "could care less" implies the speaker cares a bit more than not at all, and they could still drop to absolute zero in caring but have not yet.

@ J.Alexandre - Thanks for your reply, which was rather more diplomatic than my comment. Talking of oxymorons, my English teacher's favourite expression was "Now, then he said, giving me a pretty ugly look", and I'm reminded we also have the expression "a deafening silence". English is just like that sometimes.

I appreciate the response, Will, and while I don't disagree that it's efficient (like you said, it's only two words) I suppose I take most offense with the words themselves, 'Same' and 'Difference',which to my ear sound oxymoronic.

The Longman Dictionary example you provided does highlight it's best application to me, but it still sounds off.I guess the most I can do is be dissatisfied with its saturation, but I appreciate you clearing it up for me.

First of all it's an idiom, so it doesn't really need much justification. And in any case it's only used informally; nobody's going to write it in an academic essay!

But secondly, it's far from meaningless; it's like saying - "Well, these two things (whatever they are) may look different, but as far as I'm concerned they're more or less the same." - "same difference" makes perfect sense in this context. And it's efficient - just two words.

Example form Longman Dictionary - 'I could mail the letter or send a fax in the morning.' - 'Same difference. It still won't get there on time.'

It's a bit like saying "six one, half a dozen the other" - another colloquial expression which needs no justification, or do you think that's "a junk phras" too?

"Is there any validity in this phrase, outside modern colloquialism?" - isn't modern colloquialism validity enough? And it can hardly be meaningless when everyone understands what it means.